Seriously, though, WHY would Noam Chomsky be one of the top 20
Scientists of the century. Most of his academic work extends the work
of a much more significant figure in social theory, Marshall McLuhan.
Of course, he was Canadian, so who really cares...

I'd give Noam a "Top 20 Social Activists" award but nothing beyond
that. I don't think I'd even give McLuhan himself the nod as a Top
scientist, since judging by the other contributors the key to this list
is invention, and he has never really invented anything. McLuhan, later
replaced by Chomsky, just broadened our understanding of the world and
gave us a context within which to view it.